As the demand for electricity grows, there is an increased need for higher capacity electricity transmission and distribution lines. The amount of power a transmission line can deliver is dependent on the current-carrying capacity (ampacity) of the line. Such ampacity is limited, however, by the maximum safe operating temperature of the bare conductor that carries the current. Exceeding this temperature can result in damage to the conductor or other components of the transmission line. However, the electrical resistance of the conductor increases as the conductor rises in temperature or power load. A transmission line with a coating that reduces the operating temperature of a conductor would allow for a transmission line with lowered electrical resistance, increased ampacity, and the capacity to deliver larger quantities of power to consumers. Therefore, there is a need for a polymeric coating layer that has a low absorptivity in order to limit the amount of heat absorbed from solar radiation, a high thermal conductivity and emissivity in order to increase the amount of heat emitted away from the conductor, a high thermal resistance and heat aging resistance to boost life span and survival at high conductor temperatures, and which can be produced in a continuous and solvent-free process.